Children's soft toys can harbour high levels of cat and dog allergens as well as house dust mite allergens, according to new research by the University of Otago, Wellington.
After house dust mite allergens, exposure to cat and dog allergens is the next most common indoors. All are strongly associated with asthma.
Children often sleep with soft toys close to their airways, so any allergens present can be a potential problem for asthmatics, says Associate Professor Rob Siebers.
"What that means is that exposure to allergens on toys tends to be great than exposure to mattresses," Professor Siebers says.
The study analysed dust collected from 40 children's soft toys and mattresses. Most had detectable cat and dog allergen levels even in homes without cats or dogs.
Thirty-five of the 40 soft toys (87.5%) had detectable cat allergen levels, and 34 (85%) had detectable dog allergen levels. By comparison, 80% of mattresses had detectable levels of the allergens.
Furthermore, while all mattresses and soft toys had detectable house dust might allergen levels, soft toys contained about three times the level of those on mattresses.
While soft toys have long been recognised as a source of house dust mite allergens, this is the first major study of its kind to confirm they are also a source of cat and dog allergens, regardless of whether the home has pets, Professor Siebers says.
"Cat and dog allergens are aerodynamic and can be transported on clothing into animal-free areas, even in cat-free areas such as the Antarctic."
Professor Siebers says the good news is that a regular cold wash in the washing machine has been proven to get rid of cat and dog allergens.
"My advice to parents, particularly of children who are sensitised asthmatics, is to put the toy their child sleeps with through the wash at least weekly."
The research has just been published in the online Journal of Asthma, and was carried out in association with colleagues at the Show Chwan Memorial and Changhua Christian hospitals in Taiwan.
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